Internal abrasive device



Jan, 20, 1948. M. C. HUTTO 2,434,801

INTERNAL ABRASIVE DEVICE Filed June 20, 1946 r 3 Sheets-Sheet l INVENTOR M/J/FSDt'N CHUTTU Ms ATTORNEYS Jan. 20, 1948. MIC. 1 m 2,434,801

INTERNAL ARASIVE DEVICE Filed June 20, 1946 s Sheets-Sheet 2 INVENTOR Mfl/PSDEN CI HU7'7'0 H ATTORNEYS Jan. 20, 1948. I M, c, HUTTO 2,434,801

INTERNAL ABRASIVE DEVICE Filed June 20, 1946 s Sheets-Shes s lNVENTOR MHASDEN 6. H0 rro BY 2mg,

H": ATTORNEY$ A Patented Jan. 20, 1948 INTERNAL ABRASIVE DEVICE Marsden C. Hutto, Detroit, Mich., assignor to Vinco Corporation, Detroit, Mich., a corporation of Michigan Application June 20, 1946, Serial No. 678,112

6 Claims.

This invention relates to abrading apparatus for finishing cylindrical and curved surfaces. More particularly, it is concerned with a honing head wherein the radial position of the honing or finishing elements is adjustable to a fixed, working diameten.

In certainzf nishing operations, it is desirable to accurately qfinishourved surfaces to the desired size and contour by means of abrading surfaces of predetermined, fixed, efiective diameters, Ordinary honing heads incorporating pre-set finishing elements present problems of accurate truing of honing stones to the correct contour, maintenance of the latter within close limits despite wear, and inherent inflexibility as to radial dimension of the articles to be finished. An important object of this invention, accordingly, is to provide a honing or finishin fixture with individually adjustable abrasive elements, thus facilitating fine adjustment and correction of the Working diameter as well as permitting variation in the size of the work objects.

The apparatus of the present invention may be advantageously employed as a honing head in the finishing of resiliently expansible circular articles such as piston rings. Such rings may be finished while they are expanding radially under their inherent resilience into yielding engagement with an internal honing or finishing device which embraces their peripheral surfaces, so that the rings will be finished to the exact shape or contour that they should have in order to fit tightly and continuously against the walls of a cylinder which they expansively engaged under operating conditions. Manifestly, a finishing device of accurately predetermined internal diameter is required in this method. Moreover, a device wherein adjustment of the diameter of the internal abrasive surfaces may be secured, and wherein such abrasive elements may be retracted from or contracted to the working fit is highly desirable. For purposes of illustration, therefore, the present invention is depicted and described in an embodiment suitable for use in piston ring honing apparatus. It is understood that this is merely one application for which this invention is adapted, and is in no sense intended as a restriction of the scope of the invention.

Another object of the invention is to provide a simple mechanism for adjusting abrasive elements within easy control of the ordinary operator. Other specific objects and advantages will appear from the ensuing description of an embodiment of the invention which is illustrated in the accompanying drawings. In the drawings,

Fig. 1 represents an end elevation, partly in section, of a honing head embodying the invention.

Fig. 2 is a sectional view taken along the line 2-2 of Fig, 1 and viewed in the direction of the arrows.

Fig. 3 is a sectional view taken along the line 3-3 of Fig. 2; and

Fig. 4 is a sectional view taken along the line 4-4 of Fig. 2.

Referring to Fig. 2, it will be seen that in the illustrated embodiment, four abrasive or honing elements or stones 6 with individual adjusting units are symmetrically disposed in the main frame or mounting 5 of the finishing fixture which surrounds the articles to be finished. As shown, the inner faces of the abrasive stones 6 are arcuate so as to present a series of internal arcuate abrasive surfaces disposed along a. cylindrical path of a diameter preferably equal to that of the cylinder in which the piston rings to be finished are to operate. A work shaft 1 and ring supporting mechanism 8 are shown in Fig. 1 in working position within the finishing fixture, and these parts may be of the construction described in detail in my co-pending application Serial No. 614,893, filed September 7, 1945, entitled Honing method and apparatus, now Patent N 0. 2,422,418, dated June 17, 1947.

Each individual abrasive stone 6 is affixed advantageously by cement or other adhesive means to a stone holder plate 9, Each stone holder plate 9, in turn, is fastened, as by bolting, to a stone holder piston H) which is slidably disposed in a suitable opening in a radial extension ll) of the main frame 5. The wall of the piston rides against a felt washer H held in place by a retainer ring l2 secured to the inner end of the frame extension I0;

Movement of the stone holder piston Ill relative to the frame 5 is effected by an adjusting screw i3 which engages a threaded adjustment nut l4 secured in an elongated central cavity [5 within the piston H). An end cap I6 is aflixed to the main frame 5 over the piston unit advantageously by a plurality of screws.

A knurled disc I! for manual adjustment of the screw is fixed to the adjusting screw l3. A collar 30 integral with the screw 13 engages the under surface of the cap l6 and the disc I! engages the outer cap surface, whereby the screw I3 is held against longitudinal movement and its rotation propels the piston I 0. A graduated ring I8 is clamped to the knurled disc I! by a clamp ring I9 and a plurality of screws 20. The initial positions of the abrasive elements 6 can be made to correspond with the zero positions of the graduated rings by loosening the screws 20 and setting the graduated rings l8 to the desired positions, and the movement of the disc can be determined by the movement of the ring graduations past an index mark 3! on the cap [6. Thereafter, the amount that the knurleddiscs I! are turned in adjusting the stones may be read directly. A retaining collar 2| fits over the knurled disc I! and the adjusting screw l3, and is attached by a screw 22 to the latter.

Means for locking the piston ID in position during grinding is illustrated in Figs. 2 and 3. Two shoes, 23 and 24, preferably of brass, engage spaced portions of the pistons periphery. The shoe 23 is unthreaded and the shoe 2 is internally threaded so that tightening the knob 25 of the threaded bolt 26 causes the shoe -24 to grip the piston against th shoe 23 which is held by a shoulder on the bolt 26. In this manner, dislocation of the piston lil during the abrading operation is prevented. When it is desired to adjust the position of the abrasive stone, the clamp knob 25 is loosened, releasing the pressure of shoes 23 and 24 upon the piston it.

To eliminate rotation of the stone holder piston during adjustment, a U-shaped guide 2'1" is afiixed thereto by a plurality of bolts, and slidably engages a guide block 28, which is integral with or fastened to the frame 5 (Figs. 2 and 4). Thus the rotation of the adjusting screw 13 is translated into axial movement of the piston l0 without accompanying piston rotation.

In operation, preparatory to grinding, the clamp knobs 25 are loosened so as to allow movement of the pistons Hi. The abrasive elements 6 may then be set to the correct positions against a suitable gauge by rotation of the screws [3, and thereafter the'graduated rings i 8 may be set to zero positions by loosening the clamp screws 28, turning the rings I8 and retightening the screws. After the abrasive elements 6 become Worn in use, they may be advanced radially inward to the proper positions by the described adjusting means.

I claim:

1. In a device for finishing cylindrical articles, the combination of an external frame surrounding the location of the articles to be finished, a plurality of pistons mounted at circumferentially spaced points in said frame and movable radially of the axis of such location, a finishing element afiixed to the inner end of each piston so as to present a series of internal, cylindrically aligned finishing surfaces with a working diameter of predetermined size, a threaded adjusting nut secured to eachof said pistons, an adjusting screw engaging each of said adjusting nuts and held against longitudinal movement relative to said frame, means forv preventing rotation of said pistons relative to said frame, and releasable means for clamping. said pistons against movement.

2. In a device for finishing. radially expansible cylindrical articles, the combination of an external frame surrounding the location of the articles to be finished, a plurality of pistons mounted at circumferentially spaced points in said frame and movable radially of the axis of such location, a finishing element afiixed to the inner end of each piston so as to present a series of. internal, cylindrically aligned. finishing surfaces witha Working diameter 'of predetermined size, a threaded adjusting nut secured to each piston, an adjusting screw engaging each of said adjusting nuts and held against longitudinal movement relative to said frame, means for preventing rotation of said pistons relative to said frame, and releasable means for clamping each of said pistons against movement comprising pair of clamp shoes movable laterally of said piston and means for moving said shoes ,into clamping engagement with spaced points on said piston.

3. In a device for finishing radially expansible cylindrical articles, the combination of an external frame surrounding the location of the articles to be finished, a plurality of pistons mounted at circumferentially spaced points in said frame and movable radially of the axis of such location, a finishing element afiixed to the inner end of each piston so as to present a series of internal, cylindrically aligned finishing surfaces with a working diameter of predetermined size, a threaded adjusting nut secured to each piston, an adjusting screw engaging each of said adjusting nuts and held against longitudinal movement relative to said frame, means for preventing rotation of said pistons relative to said frame, and releasable means for clamping each of said pistons against movement comprising a'pair of clamp shoes movable laterally of said piston, a screw mounted in the frame threadedly engaging one of said shoes and a collar on said screw for limiting the movement of the other of said shoes.

4. In a device for finishing radially expansible cylindrical articles, the combination of an external, substantially circular frame surrounding the location of the articles to be finished, a plurality of pistons mounted at symmetrically spaced points circumferentially of said frame and movable radially of the axis of such location, a finishing element afifixed to the inner end of each of said pistons so as to present a series of internal, cylindrically aligned finishing surfaces with a working diameter of a predetermined size, a threaded adjusting nut secured to each piston, an adjusting screw engaging each of said adjusting nuts and held against longitudinal movement relative to the frame, means for preventing rotation of each of said pistons relative to said frame comprising a guide affixed to said piston and a block secured to the frame slidably engaged by said guide, and releasable means for clamping each of said pistons against movement comprising a pair of clamp shoes movable, laterally of said piston and means'for movingsaid shoes into clamping engagement with spaced points on said piston.

5. In, a device for finishing. radially. expansible cylindrical articles, the combination of an external, substantially circular frame surrounding the location of the articles to be finished, a plurality of pistons mounted at circumferential and symmetrically spaced points in said frame and movable radially of the axis of such location, a, finishing element afiixed to the inner end of each of said pistons so as to present a series of internal, cylindrically aligned finishing surfaces with a working diameter. of a predetermined size, a threaded adjusting. nut secured to each piston, an adjusting screw. engaging each ofsaid adjusting nuts and held against longitudinal movement relative to the frame, means for preventing rotation of each of said pistons relative to saidframe,

and. a graduated scale fixed to each of said adjusting screws for indicating the rotatio'n thereof.

6. In a device for finishing radially expansible cylindrical articles, the combination of an external, substantially circular frame surrounding the location of the articles to be finished, a plurality of pistons mounted at circumferential andsymmetrically spaced points in said frame and movable radially of the axis of such location, a finishing element amxed to the inner end of each of said pistons so as to present a series of internal, cylindrically aligned finishing surfaces with a graduated scale fixed to each of said adjusting screws for indicating the rotation thereof, and means for adjusting the position of said scale relative to said screw,

MARSDEN C. HUTTO.

REFERENCES CITED The following references are of record in the file of this patent: working diameter of a predetermined size, a

UNITED STATES PATENTS Number Name Date 1,056,212 Piersteien Mar. 18, 1913 15 1,827,789 Hutto Oct. 20, 1931 2,138,257 Sievers, Jr Nov. 29, 1938 2,318,837 Connor May 11, 1943 FOREIGN PATENTS Number Country Date 322,950 Great Britain Dec. 19, 1929 

